The present disclosure generally relates to methods and compositions for reducing inflammation, and more particularly, to compositions comprising oleocanthal. The oleocanthal-containing compositions are particularly suitable for transdermal delivery.
Topical routes of drug administration are often desirable because problems associated with other drug delivery means can be avoided. For instance, oral administration of drugs is often associated with variable absorption and metabolism of the drug and gastrointestinal irritation. In particular, the gastrointestinal irritation associated with the oral administration of non-steroidal anti-inflammatory drugs (NSAIDs), such as aspirin, ibuprofen, and naproxen, among others, is well documented. In an effort to overcome the drawbacks of oral administration of NSAIDs, an ibuprofen based cream was recently introduced that can be applied directly to skin above the source of inflammation. Although such a cream may avoid some of the traditional problems associated with administration of NSAIDs (e.g., gastrointestinal irritation), there are other problems associated with transdermal administration of these drugs.
For instance, the skin provides a protective barrier against foreign materials and infections and helps protect the body from water loss. The layer of skin primarily responsible for this barrier function is the epidermis, and more particularly, the uppermost layer of the epidermis (i.e., the stratum corneum or horny layer). In mammals, the stratum corneum consists of horny skin cells (i.e., corneocytes) embedded in a lipid matrix. This structure is often referred to as a “brick and mortar” model, with the corneocytes being the “bricks” and the epidermal lipids being the “mortar.” The structure of the stratum corneum provides a strong barrier to the diffusion of molecules through the skin, often restricting diffusion through the skin to molecules having a certain size, solubility, and/or lipophilicity. This presents a problem for the diffusion of certain NSAIDs, such as ibuprofen, which have a relatively low solubility in fats and oils, and under certain conditions may precipitate and form an insoluble salt.
There is thus a need for compositions useful for the relief of inflammation that may be effectively delivered transdermally.